Compare ipblock (#88)

pkg/netset/ipblock.go

@@ -152,6 +152,22 @@ func (b *IPBlock) IsSingleIPAddress() bool {
 	return b.ipRange.IsSingleNumber()
 }
 
+// Compare returns -1 if this<other, 1 if this>other, 0 o.w.
+func (b *IPBlock) Compare(other *IPBlock) int {
+	switch {
+	case b.ipRange.Min() < other.ipRange.Min():
+		return -1
+	case b.ipRange.Min() > other.ipRange.Min():
+		return 1
+	case b.ipRange.Max() < other.ipRange.Max():
+		return -1
+	case b.ipRange.Max() > other.ipRange.Max():
+		return 1
+	default:
+		return 0
+	}
+}
+
 // Split returns a set of IPBlock objects, each with a single range of ips
 func (b *IPBlock) Split() []*IPBlock {
 	intervals := b.ipRange.Intervals()

pkg/netset/ipblock_test.go

@@ -42,12 +42,12 @@ func TestOps(t *testing.T) {
 	intersect2 := minus.Intersect(intersect)
 	require.True(t, intersect2.IsEmpty())
 
-	ipb3, err := ipb2.NextIP()
+	ipb3, err := ipb2.NextIP() // ipb3 = 1.2.3.5
 	ipb4, _ := netset.IPBlockFromCidrOrAddress("1.2.3.5")
 	require.Nil(t, err)
 	require.Equal(t, ipb3, ipb4)
 
-	ipb5, err := ipb3.PreviousIP()
+	ipb5, err := ipb3.PreviousIP() // ipb5 = 1.2.3.4
 	require.Nil(t, err)
 	require.Equal(t, ipb2, ipb5)
 
@@ -79,6 +79,10 @@ func TestOps(t *testing.T) {
 	require.False(t, t2)
 
 	require.Equal(t, ipb7, ipb7.FirstIPAddressObject())
+
+	require.Equal(t, ipb5.Compare(ipb6), -1)
+	require.Equal(t, ipb2.Compare(ipb1), 1)
+	require.Equal(t, ipb3.Compare(ipb4), 0)
 }
 
 func TestConversions(t *testing.T) {